Oven or furnace



GL M. HOLLENBACK.

OVEN 0H FURNACE.

APPLICATION FILED JULY 11.1918- v Patented Feb. 24, 1920.

j UNITED STATES' STENT OFFICE.

eiiozfon'iif. ifnninlick, or zt'fevvisrowir, MONTAA'.

ovni@ on FURN'ACE.

isernia.

Tofall'whom 'it may cimemf: Y

Be it known that I, GEoRGnM. HoLLEN BACK, a, citizen ofthe United States, residing at Lewistown, in the county of Fergus and State of Montana, have invented new and useful Improvements" in Ovens or Furnaces, of which the following isa specification.

This invention relates to ovens orV furnaces, and it has for its object to provide an oven lor furnace, for use in'connection with dental and other operations, and whereby an obj ect'orwork of any kind'inay be Subj eeted to heat at a predetermined temperature, for a predetermined period of time. vIt will be obviousthat an oven'or furnace so organized is capable of use for a wide range ofpurposes',` and throughoutv a wide range of tne arts', and it is particularly'usefulfor subjecting to heat, in the art of dentistry, flasks containing wak models invested in initially plastic material, and from which investment such wak vor the like is tobeburnt out to leave` the` mold in which inlays, crowns, bridges and the' like, may be' cast. The invention 'has'for further objects vthe provision of improved ovens-or furnaces of the general character stated, whichwill vbe superior in point of relativeusimplicity and inexpen' siveriessj of construction, takenin connection withreliability, and accuracy and positiveness in operation, automatic performance, convenience( in use and adjustment, comp'a'ctness in form anddurabilitv` and which will, be generally superior in eliiciency and srviceability.

Withthe above and other obj ects in View, they invention consists in the novelfand use ful provision, formation, construction, combination, association, and relative arrangement of"parts,"me mbers andfea'ture's, all as hereinafter described, shown in the Vdrawing, and finally pointed out in claims.

In the drawing' Figure 1I isa centrallongitudinal sectional v'ievv, partlyin elevation, of oven or furnace mechanism, constructed Aand organized to embodyhthe inventiong` Fig. 2 isa detaillvievv 4offpartsof-the' pen'- dullum and associated parts;A

Fig. 3 is asimilar view of the work supporting carriage;

Fig.' 4; is a plan view of the adjustable end standard; l

Fig; 5 is ad'e'tailview of the-electric ymake an'd'lhrealzjdevi'ce-whieh is actuated by thel rig. 7 is an enlarged dean View, phenny sbicit'ion of Letters raten. Patented Feb; 24, 1920, Applieauon' mea July 11, 191s; serial No. 244,466.

in section,` of the bearing at one end of the threaded shaft.

Corresponding parts in all the figures are designated by the same reference characters.

Referring with particularity to the drawing, the improved furnace or oven Inecha-` nism therein shown comprises in the main an oven or furnace working chamber A which is provided in a casing 7 having throughout a heat insulating lining, as indicated at 8, on its top closure 9, which is detachable, and through which projects a 'temperaturefindicating device, such as a thermometer h with its bulb and a mercury bathu; The. casing 7 isopen at itsl ends, and ranging lengthwise thereof through the chamber A is a threadedshaft b for feeding ori advancing through such chamber Aan object,` article' or work. C to' be subjected toV heat einanatingfrom heat producing means 10 disposed beneath ,the bottom member 7 a' of tlie casing 7. Such, heat producing means are indicated as an electricalzresistance coil in circuit withiwhich is a thermostatic device VE disposed within the chamber A, and adapted to cause the intermittent energizationfof the coil 10 so as to maintain a constatutl temperature within the chamber A. FV designates a source of electricalenergy for the coil 10 and also for the work ad-` vancing means. In the present construction A the threaded shaft b isrintermittently rotated to advancefthework C which is sup'- ported by a'trav'eler or carriagelQhaving athreaded. knuckle v13 whichA interengages" withthe threadsof the member or shaft b, sojthat the traveler 12 lmoves lengthwise through 'the chamber VA when the shaft is rotated. The means for rotating the shaft comprises a ratchet wheel 14 loose upon a stub shaft 15, there being a` pendulum 16V fulcrumed upon such stub shaft, as at 17, and carrying adog. 18 adapted to intermittently rotatethe'ratchet wheel 14 as the pendulum oscillated such pendulum be'- ing actuated -by an electro-magnet `19 ener+ gized from the source of electrical energy F,

a transformer being included in the'circuit between such source of electrical energy and the electro-magnet, for thepurpose-Of reducingythe voltage. .v Included-1 withinsuch' l electrical 3circuit" mipplying: the electrofmagl net 19, is a make and break device, which consists of a contact terminal adapted to be intermittently engaged by a sliding contact device 21 mounted in a suitable slideway-22, and having spaced actuating pinsQ-S arranged to be alternately engaged by an insulated portion 24 of the pendulum 16.

The end of the shaft b remote fromthe.

ratchet Wheel 14 has the pivot bearing 11, the same co-acting with a stub shaft 25, supportedby a standard 26. The Vother end of such shaft b has a pivot bearing connection as at 27 with the stub shaft 15; and a collar 28 fast upon the shaft b at the latter end is connected operatively with the ratchet wheel 14 by angular arms 29, so that the shaft Z) turns with the ratchet wheel.

The arms 29 are loosely received within openings 30 in the ratchet wheel 14, and the point bearings at l1 and 27 may be tightened or loosened by adjustment of the standard 26 with its stub shaft 25, such standard having a slotted foot 31 through which passes a threaded bolt 32 fixed in a base block'33,

vand having a thumb nut 34 whereby the foot V31 may bev bound doWn in position of adjustment.

They operation, method of use and advantagesof the improved oven or furnace mechanism constituting the invention, will be readily understood, with all of its adaptabilities to varying kinds and conditions and characters of use and service, by thosey which intermittently rotates the ratchetV wheel is oscillated Vunder influence of the electro-magnet 19, which co-acts. with an armature 19a upon the pendulum, the electro-magnet being intermittently energized and denergized through the action of the circuit maker and breaker. Thus the ratchet wheel 14 isV intermittently turned by the dog 18 and the shaft b intermittently rotated to advance the work C stepY by step through theV chamber A, at a rate of speed'predetermined and predicated upon the operation of the ratchet wheel and pendulum. The

`temperature of the. heat producing means D is likewise predetermined, and may be maintained by the thermostatic element E orl voluntarily through a suitable switch or' controlling member in accordance with readings of thethermometer h. The length of the chamber A is a denite quantity, and

thus, inter-calculating all of these factors of chamber length, speed of carriage movement and degree of heat, the total application of heat to the work may be definitely predetermined and controlled.

Thus, the work C may issue from the chamber A accurately and completely aected by heat aspredetermined, as for instance, with the waX model in the mold in the dental flask entirely eliminated by heat action. The dentist or operator or attendant may thus maintain a sequence of heating performances with respect to a plurality ofV specimens of work, each carrier 12 being open atone side so that it may. be readily placed upon or removed from the shaft I). It is evident that the heat produced by the coil 10 may be varied by changing the resistance thereof, or the amount of electricalv energy supplied thereto, and the rate of travel of the work through the chamber A may be varied by substituting shafts b of` varying pitches of thread or this result may be accomplished by varying the stroke of the pendulum. v

It is obvious that the use of, mechanism or apparatus of the character disclosed makes for accuracy in performance, com-k bined with convenience in control andautomatic performance, and that many variations or modificationsv and alterations and substitutions maybe made, with respect vto the specific apparatus pictured and de-k` scribed, in adapting the invention to varying` conditions of use and service, without departing from the true spirit of the invention. f Having thus disclosed my invention, I claim and desire to secure by Letters Patent:

1. A device of the character described, in-

cluding a heating chamber, a work supporting carriage mounted to move through the chamber, an oscillating device, means actu-- ated by the oscillating device for advancing the carriage through the chamber, and an electro-magnet together with a make and break device associated with the oscillating member for actuating the same. 2. Improvements of the character disclosed, comprising a heating chamber, a threaded shaft ranging through said heating chamber, a carriage adapted to traverse said shaft, and means for moving said carriage lengthwise of said shaft through said heating chamber; said latter means comprising an oscillating element, a rotating element operatively connected with said shaft, and means for converting the movements of Vsaid oscillating element into step by step rotation of said rotating element.

3. Improvements of the character dis-` closed, comprising a heating chamber, a threaded shaft ranging through said heating chamber, acarriage adapted lto traversev said shaft, and means for moving said carriage lengthwise of said shaft through said heat-V ing chamber; said means comprising an oscillating element, a rotating element for said shaft and receiving its actuation from said oscillating element, and electro-magnetic means for operating said oscillating element. Y

4. Improvements of the character disclosed, comprising a heating chamber, a threaded shaft ranging through said heating chamber, a carriage adapted to traverse said shaft, and means for moving said carriage lengthwise of said shaft through said heating chamber; said means comprising yan oscillating element, a rotating element for said shaft and actuated by said oscillating element, an electro-magnet, and a make and break device in circuit with said electromagnet and controlled by said oscillating element, said oscillating element having an armature for acting responsive to energization of said electro-magnet.

5. Improvements vof the character disclosed, comprising a heating chamber, a

threaded shaft ranging through said heating chamber, a carriage adapted to traverse said shaft, and means for moving said carriage lengthwise of said shaft through said heating chamber; said means comprising an oscillating element, a rotating element for said shaft and actuated by said oscillating element, an electro-magnet, and a make and break device in circuit with said electromagnet and controlled by said oscillating element, said oscillating element having an armature for acting responsive t energization of said electro-magnet; said make and break device comprising a Xed contact device and a sliding contact device with the latter of which said oscillating element Vis intermittently engaged.

In testimony whereof, I have signed my naine to this specification in the presence of two subscribing witnesses.

GEORGE M. HOLLENBACK.

Vitnesses: Y

RAYMOND IvEs BLAKESLEE, MILDRED LEACH. 

